Call a function before reseting by NRST

[dmatheis]

Posted on July 20, 2009 at 12:38

Call a function before reseting by NRST

[dmatheis]

Posted on May 17, 2011 at 13:18

Hello,

is it possible to call a function before the NRST-Pin resets the hole system (e.g. to save some data in an external eeprom)? Is there any IRQ-Handler which could be called when pressing the switch connected to my NRST-Pin? Thank you :D

[sofiene]

Posted on May 17, 2011 at 13:18

Hi dmatheis;

You can use EXTI interrupt instead of NRST-Pin to reset the microcontroller. How? So you can connect a button in any EXTI. In the EXTI handler you can save your data and after that call NVIC_GenerateSystemReset() (software reset). B.R. M3allem

[dmatheis]

Posted on May 17, 2011 at 13:18

Hi M3allem,

thanks for your replay, but I'm searching for a solution to get the beheavior/functionality of the EXTI also on the NRST pin. :-]

[swhite]

Posted on May 17, 2011 at 13:18

A reset is a hardware condition that can't be trapped like a normal exception.

That said you can determine the cause of a reset *after* it has happened. See the ST Library function RCC_GetFlagStatus(). I do this in a current project to display/log the last reset cause along with additional information. Makes a great firmware/hardware debugging feature 🙂 Edit: You can (and I do) get indication of a power failure and do stuff *before* you reset.[ This message was edited by: swhite on 20-07-2009 16:09 ]